Enciphering and deciphering mechanism



April22, 1924.

H. PFANNENSTIEHL ENCIPHER ING AND DECIPHERING MECHANISM Fil ed Dec. 28 1918 4 Sheets-Sheet l Apfil 22 1924.

, H. PFANNENSTIEHL ENCIPHERING AND DEGIPHERING MECHANISM I Filed Dec. 28 1918 4 Sheets-Shet 5 y? My;

H. PFANNENSTIEHL ENCIPHERINQ AND DECIPHERING MECHANISM April 22 1924.

far:

4 Sheets-Sheet 4 /n en Harry Pfann'ensfieh/ by Filed Dec. 28 1918 m n u m u n a I n n I Patented Apr. 22, 1924.

PATENT OFFICE.

UNITED STATES HARRY PFANNENSTLEHL, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

ENCIPHERING AND DECIPHERING MECHANISM.

Application filed December as, 1918. Serial No. 268,677.

To all whom it may concern:

Be it known that I, HARRY PFANNEN- srmnn, a citizen of United States, residing at East Orange, in the county of Essex, State of New Jersey, have invented certain new and useful Improvements in Enciphering and Deciphering Mechanism, of which the.

following is a full, clear, concise, and exact description.

'This invention relates to signal controlling apparatus and particularly to selecting mechanism for use with such apparatus.

The principal object of this invention is to provide an improved mechanism whereby 1 a given or definite number of elements may be selectively controlled or-arranged in different combinations in a reliable and eflicacious manner. The invention is applicable to enciphering systems, deciphering systems, telegraph systems, and the like.

In the particular embodiment herein chosen for illustration, the invention is applied to a deciphering device whereby asecret or enciphered message may be deciphered automatically and the true message indicated in code form. More specifically the invention comprises a plurality of selecting and selectable members, each of the selectable members being arranged to control the movement of an element associated therewith. The selecting members may he controlled by manually operable keys or they may be selectively controlled by a perforated tape or the like.

It has previously been proposed to employ, in connection with printing telegraph system, a method of enciphering the message to be transmitted which consists in transmitting over the line for each character of the message a set of impulses which represents the combination of the true message impulses with a second set of impulses arbitrarily chosen and changing for each character transmitted.

Such a result has been obtained by perforating the true message on a paper' strip or tape in the form of the well known Baudot code, perforating a similar tape with another message or jumble of characters, running these two tapes in synchronism through two tape transmitters which jointly control the transmission of impulses to the line or the energization of the electromagnetic punch selecting members of a local perforator which perforates a third tape with an unlntelhgible sequence of characters representing a combination of the message tape and the cipher tape. This unintelligible or enciphered message is then transmitted over the line and may be recorded by any suitable receiving device, preferably a receiving perforator which will then perforate a tape duplicating that used for the transmission of the enciphered message.

For deciphering such a message it is essential that the receiving operator be provided with a duplicate of the original cipher tape. \Vhen so equipped, he can by running-the cipher tape and the enciphered message tape in synchronism through two local tape transmitters, excrta joint control on the selectingmechanism of a local printer that will result in the printing of the original message in deciphered form.

Further secrecy of communication can be secured by employing two (or more) ciphering tapes simultaneously and combining the effects of the two with the message tape. The invention herein involved in theform chosen for illustration, provides a mechanical device for deciphering a message transmitted according to the system above outlined and suitable for use in situations where electrical appliances are not available or ordinarily operable. The specific form herein illustrated comprises four sets of movable shutters, one set for each impulse element of a four impulse code. Each set is composed of three shutters each of which is provided with a plurality of openings which are so disposed with reference to the openings of the other shutters of that set that a clear path for a beam of light will be provided if an odd number of the shutters of the set are shifted from normal position but no such path will be provided if an even number of the shutters are shifted. The shutters may be shifted selectively under the control of three control devices to each of which is assigned the control of one shutter of each set.

Two of these control devices are set for operation by means of perforated tapes, in this case the two cipher tapes, while the third control device is set for operation through the instrumentality-of a set of manually operated keys, in accordance with the signal indication appearing on the enciphered message tape. When all three control devices have been thus set, the actuation of a single operating key moves thevarious selected shutters and gives a direct visual indication in code of the deciphered message. The release of the operating key moves the two cipher tapes along for the next character, and restores the shutters to normal preparatory to the deciphering of the next character of the message. The true message may thus be spelled out character by character without the necessity of reference to an elaborate code book.

The invention will be more readily understood ,from the following detailed description and claims, and by reference to the accompanying drawings illustrating thepreferred form of applicants invention, wherein, Fig. 1 is a plan view of the decipherin instrument; Fig. 2 is a horizontal sectiona view showing the arrangement of the selecting and selectable bars; Fig. 3 is a vertical sectional-view along the line 33, Fig. 1; Fig. 4 illustrates an arrangement of the various shutters, carried by the selectable bars, necessary to give thevisual indication represented in Fig. 1; Fig. 5 is a vertical sectional view of one of the tape controlled mechanism in unac'tuated position; Fig. 6 is ,another vertical sectional view of the mechanism illustrated in Fig. 5, but shown in actuated position; Fig. 7 is a vertical sectional view taken along the line 77 Fig. 2; Fig. 8 is-a partial view of the selectable bar illustrated in Fig. 7 but shown in its actuated position; and Fig. 9 represents a section of the enciphered message tape.

Referring particularly to Figs. 1, 2 and 3,

. the. deciphering instrument is enclosed in a rectangular frame structure'10, and the operating members and apparatus are supported primarily by the frame 10 and cross members 11 and 12. The selectable bars are arranged in three groups of four each. The outer groups 13 and 15 in the present embodiment are controlled by means of perforated tapes, while the bars of the center group 14 are controlled by manually-operable keys,

31, there being one key corresponding to each selectable bar of the key controlled group. Each selectable bar of each group carries a shutter which is provided with a plurality of openings therein and the shuttors are arranged in four sets of three each. In the embodiment shown, each shutter is provided with four openings and the open ings are so disposed that normally no set of shutters are arranged so that openings therein fall in alignment, but when the shutters are selectively actuated in accordance with predetermined conditions, the shutters will present one or more sets of holes in alignment, so that a clear path for a beam of light is provided. For convenience in reading the indication. when displayed in code form, the shutters may be mounted at any suitable angle, for example, as illustrated in Fig. 3.

At the right-hand end of the instrument are mounted two similar tape controlled devices best illustrated in Figs. 5 and 6 One of the tape controlled devices controls the selective action of the selectable bars forming the group 13, while the other device controls the selective action of the group of bars 15. The tape controlled devices are in general similar in structure to the wellknown automatic tape transmitters employed for transmitting signaling impulses, and in the form herein illustrated, the devices difi'er from the usual tape transmitters only in that the selecting pins determine the movement of selectable shutter-carrying members instead of closing contacts. perforated cipher tapes are each fed forward by a feed wheel 17. provided with a plurality of radially extending pins which cooperate with the row of feed holes punched longitudinally in the center of the tape. The feed wheel is mounted on a shaft 18, to which is rigidly secured a ratchet wheel 19. The shaft is rotated by a feeding pawl 20 cooperating with the ratchet, the

.operation of which will presently be described. To prevent backward rotation of the ratchet and feed wheel, a jockey roller 21 is provided which permits the ratchet to be turned in one direction only. Arranged just beneath and crosswise of each tape are four vertically mounted members 22, ta-

pered at the upper ends into selecting pinsv and adapted to cooperate or register with the holes in the tape to thereby determine which shutters of a particular group are to be actuated.

The pins are normally held spring-pressed against the tapein readiness to register with the openings therein the instant they appear over the pins. Associated with each pin member 22 and forming a Ebnhecting Thelink between each of the selectable Bars 13 j and 15 and the members 22 is a selecting member 24, normally pivoted on .a rod 25. The forward end of each member 24 is adapted to engage a shoulder or offset portion of its associated selectable bar, while the opposite end of each selecting member 24 is bifurcated and cooperates with a post or extension 23 attached to its associated selecting pin.

The selecting pins 22 and selecting members 24 are normally held in the positions indicated in full lines, Fig. 5. The parts are held in this position when there are no openings in the tape in position fo the pins to pass through. However, the instant an opening appears in the tape immediately above a selecting pin, the pin and correder the action of spring member 26 into the dotted line positions, Fig. 5, to thereby control the actuation of-one of the selectable bars 13 and 15.

The irregularly shaped rod 25 is best illustrated in Fig. 2 supported at 27 and 28. The rod 25 is normally held in its retracted or unoperated position by means of retractile spring 51, one end of which is attached to the rod 25 andthe other end to the frame 10. The rod 25 is adapted to be rocked or oscillated, for purposes as will presently appear, by the depression of operating key 43.

Referring now particularly to Figs. 1, 2, 3, 7 and 8, a plurality of manually operable finger keys 31 and key levers 32 are provided for directly controllin the actuation of the selectable bars 14. ssociated with and mounted just beneath each bar 14 but loosely connected thereto, is a parallel bar 33. Attached to each bar 33 is a. downwardly extending arm 34, which is adapted to be engaged by a rod or crank lever 35, Whenever its associated key and key lever is depressed.

Referring particularly to Fig. 7, it will be seen that when a key lever 32, is depressed, it engages an arm or extension 64 of a rod 35, and causes the rod 35 to move its corresponding bar 33 to the right as indicated in the dotted line position. When the bar 33 ismoved to the right, a pin53 carried thereby, and normally in engag ment with a pivotally mounted arm 36 carried 'by bar 14, raises the arm 36 into the dotted line position, Fig. 7, in readiness to control the movement of its associated selectable bar. It will be noted that the movement of the bar 33 does not impart motion to its associated select-able bar 14, but merely conditions the bar 14 for actuation. Each bar 33 may be provided with suitable holding means, such as V-shaped grooves 37 and 38, which are adapted to cooperate with the stationary V-shaped member 39 to hold the bars in either their actuated or unactuated positions, thereby making it unnecessary to hold a finger key depressed after it has once been actuated.

After one or more of the keys 31 have been depressed in accordance with the code representations of the enci hered message tape to determine which the selectable bars forming the group 14 are to be actuated,

and the perforated tapes have been laced in position in the tape controlled evices to permit certain selecting pins to register therewith and determine the bars 13 and which are to be selected, the operator depressesthe operating key 43, thereby causing the key lever 52 to engage the arm or extension 54 of shaft and rock the said shaft forward into the position illustrated in Figs. 6 and 8. Shaft 25 when rocked forward forces those of the selectin members 24, which have been selected, Earward against the .shoulders of the selectable bars 13 and 15, thereby forcing the bars to the left against the action of the sprin members 55 which normally hold the Ears to the right or in their unactuated positions. The shaft 25 in moving forward also engages those arms 36, carried by the selectable bars 14, which have been selected, and forces the selectable bars 14 to the left in a similar manner against the action of the spring members 55 which normally hold the bars with their stop pins 56 resting against the cross-member 12. Each of the selectable bars 14 is provided with a pin which is adapted to engage an extension arm 40 of the actuated selecting bars 33 for the purpose of returning the actuated bars 33 to normal as the bars 14 are moved to their actuated positions.

The depression of key 43 in addition to operating the selectable bars and shutters to display the true message character in code, also controls the restoration of the selecting pins and the feeding of the per forated tapes forward to present a new combination in each of the cipher tapes. Referring particularly to Figs. 5 and 6, the se lecting members 24 are normally pivoted on the shafts 25. However, when a bar 24 is selected and its forward end is brought into enga ement with its corresponding selectable ar 13 or 15, its pivotal ointshifts from rod 25 to the end of the se ectable bar and by means of the forward movement of the shaft 25 and the pull exerted on the member 24 by the spring 26, the bifurcated end of the member 24 is lowered, and in its downward movement withdraws the selecting pin from the opening in the tape. At the instant the selecting pins are withdrawn from the 'tape, the shaft 25 engages an arm 57 pivotallyqsupported at 58, and through the action of an extension arm 59, the feeding pawl 20, cooperating with theratchet 10, rotates the feed wheel 18 to feed the tape forward to present a new combination of perforations in the cipher tape for the selecting pins.

It is preferable that the key 43 be held depressed until the operator has read the signal or character displayed in code on the display board, and consequently the shaft 25 and the members controlled thereby are held in their actuated positions until the finger key 43 is released. The instant the key 43 is released, all of the selectable members 13, 14 and 15 which have been shifted are returned to normal under the action of their individual springs 55, and the various parts of the tape control selectingdevices are likewise restored to normal. As illustrated in Figs. 5 and 6, the cipher tapes are represented in Fig. 1.

fed forward by the depression of the operating key 43 to present a new cipher combination, and the selecting pinsregistering with the perforations of the new combination move into their selected position upon which may be made by. operatingone ormore of the keys 3-1 accidentally, and in order that such mistakes may be rectified before depressing the operating key 43, a finger key 42 is provided attached to a rocker arm 41 for restoring the bars 33 to normal. Each bar 33 is provided with an upwardly extending arm 40 against which the rocker arm 41 normally rests. When a bar 33 has been erroneously actuated and moved to the right, the extension 40 and rocker arm 41 is likewise moved to the right as indicated in dotted lines Fig. 7. By depressing the finger key 42 any time before depressing the operating key 43, the actuated bar 33 may be restored to normal, thereby enabling the operator to erase the error and set up the correct combination.

A better idea of-the. invention and the method of displaying the message characters in code can perhaps be obtained by considering the, positions of the shutters assumed in Fig. 4 to give the signal indication In Fig. 4 is illustrated the shutters carried by the several selectable bars and arranged in groups. Shutters 13 13", 13 and 13 forming one group are carried by bars 13, shutters 14*, 14", 14 and 14 forming a second group are carried by bars 14, and shutters 15*, 15", 15 and 15. forming a third group are carried by bars 15. The broken line on each shutter in Fig. 4 illustrates the normal position of the shutter with reference to its corresponding slot or aperture in the target.

' 1 15" and 15 of the third groupecontrolled by rforated tape 61 have en actuated. king at the shutters at each set, from front to back, none of the shutters 13*,14, or 15 of the-first set have been shifted; 'of the second set shutters 14 and 15 have been shifted; of the third set shutter 13-only has been shifted, and 'of the fourth set shutters 13 ,149, and 15 have been shifted.

of one or more cipher tapes.

memes for a beam of light, and when an even I number of shutters are shifted no such path will be provided; therefore since an odd number of shutters have been shifted only in the third arid fourth sets, signals will appear on the display board in the third and fourth positions only.

Inthe embodiment of the invention herein illustrated two cipher tapes have been employed, it being understood that these tapes are continuous and duplicates of the tapes employed at the transmitting station for combination with the true message tape. However, the invention is not limited to the use of any particular number of cipher tapes as it will be readily understood that the invention is equally applicable to the use When two or more tapes are employed they are preferably prepared with an unlike number 0 characters represented in each tape.

What is claimed is:

1. In combination with tape controlled members, a plurality of selecting members, selectable members associated therewith, an actuating member on which said selecting members are normally pivoted, and means for shifting the pivotal point of said selecting members from said actuating member to said selectable members.

2. In combination with tape controlled members, a plurality of selectlng members, selectable members associated therewith, an actuating member on which said selecting members are normally pivoted, means for shifting the pivotal point of said selecting members from said actuatin member to said selectable members, an means for actl ting said selectable members;

combination with tape controlled memb rs, a plurality of selecting members, selectable members associated therewith, an actuating member on which said selecting members are normally pivoted, means for shifting the pivotal point of' said selecting members from said actuating member to said selectable members, and key mechanism for actuating said selectable members.

4. In combination with tape controlled members, a plurality of selectlng members, selectable members associated therewith, an actuating member on which said selecting members arenormally pivoted, means for shifting the pivotal point of said selecting members from said actuating member to said selectable members, and means for 'o 7 crating said selectable members through t e instrumentality'of said selecting members.

5. In combination, a tape provided with prearranged groups of perforations therein,

selecting pins adapted to register with the tape perforations, a plurality of selectable bars, means controlled by said selecting pins for selecting predetermined ones of said selectable bars and key mechanism for actuating said selectable bars in accordance with ta e.

7 A mechanism for enciphering and deciphering a message comprising a tape provided with prearrangedgroups of perforations therein, selecting pins associated therewith, means for causing said pins to engage the perforations in the tape, a plurality of selectable members, bifurcated members con- :tI'OllGd by said selecting pins for selecting predetermined ones of said selectable members, and an all mechanical means for moving said selectable members horizontally from their normal position and withdrawing said selecting pins from engagement with the tape perforations simultaneously.

8. In combination, a tape provided with prearranged groups of preforations therein, selecting pins associated therewith, means for causing said pins to engage perforations in the tape, a plurality of selectable members controlled by said selecting pins, key mechanism, and a mechanical connection as sociated with the key mechanism for actuating the selectable members and for advancing the perforated tape simultaneously. 9. In combination, a plurality of selectable bars, signal controlling shutters carried thereby, manually operable means for conditioning predetermined ones of saidbars for actuation, automatic means for selectively conditioning predetermined ones for'actuation, and key mechanism for operating said conditioned bars simultaneously.

10. A mechanism comprising a plurality of selectable bars movable in the direction of their length, signal controlling members carried thereby, selecting members associated with predetermined ones of said bars and normally disconnected therefrom, a plurality of tape controlled devices for bringing said selecting members into engagement with said bars, manually operable means for selecting predetermined ones of said bars, and means for moving said selected. bars simultaneously in the direction of their length.

11. In combination, a plurality of selectable elements, arranged in groups, automatic means for selecting elements of one group,

manual means for selecting elements of another group, and an all mechanical means for operating the selected elements jointly.

12. In a deciphering device for translating an enciphered message into intelligence, comprising groups of selectable bars, signal controlling means carried thereby, keyboard mechanism for selecting members of one of said groups, tape governed mechanism for selecting members of another group, and a key operative directly on the selected bars of each of said groups for moving the selected members jointly.

13. A deciphering device for translating an enciphered message into intelligence, comprising a group of signal controlling members, means for selectively controllin the operation of said members in accor ance with the enciphered message characters, another group of signal controlling members, a tape controlled means governing the operation of said lastmentioned group of members, and an all mechanical means for oper ating the members of said groups jointly to give a visual indication of the true message in'code form.

14. A deciphering device for translating an enciphered message into intelligence, comprisin groups of selectablemembers, signal contro ling means carried thereby, keyboard mechanism for selecting members of one of said groups, tape governed mechanism for selecting members of the other groups, and an all mechanical connection between the members of said groups for operating said selected members ointly.

15. In a deciphering mechanism, a plurality of independent signal controlling devices, a plurality of movable elements associated with each control device, and means for operating predetermined ones of said elements in combination to give a momentary visual indication in code form. 16. In a deciphering device, a plurality of groups of signal controlling members, automatic means controlling the movement of members of one of said groups, manual means controlling the movement of members of another of said groups, and key mechanism for restoring to normal the selected ones of said last mentioned group.

17. In combination, a plurality of selectable members arranged in groups,key' mechanism for selecting the members. of'one of said groups, a plurality of tape controlled elements for selecting members of another group, and key mechanism for moving all of said selected members to a selecting position directly and simultaneously.

18. In combination, a plurality of groups of selectable members arranged in a unitary structure, manual means for selecting the members of one of said groups, automatic means for selectin the members of another of said groups, an key mechanism common to all of said members for o erating the selected ones directly and simu taneously.

19. An .enciphering and deciphering device comprising a. tape provide with pre- 5 arranged groups of perforations therein, se-

lecting pins associated therewith, means for causing said pins to engage the perforations in the tape, a plurality of selectable members controlled by said selecting pins, and re key mechanism for actuating the selecting members and advancing the perforated tape solely through the instrumentality of mechanical movements to give a visual indi- Ic)ation of the setting of such selectable mem-' ers.

In witness whereof, I hereunto subscribe my name this 27th day of December A. 1)., 1918.

HARRY PFANNENSTIEI'IL. 

